Logical Reasoning Skills: How to Test, Boost, and Undermine Arguments

Strengthen an argument

To make the conclusion more likely to be true given the premises.

Premises

The supports or reasons provided for an argument's conclusion.

Conclusion

The main claim that the argument seeks to prove.

Assumption

An unstated idea that the argument relies on to connect the premises to the conclusion.

Causal argument

An argument that asserts one event causes another.

Strengthening mechanism

Common methods include confirming assumptions, eliminating alternative explanations, and adding relevant evidence.

Evaluating arguments

Identifying what information is needed to judge whether a conclusion is well supported.

Two-way test

A method to determine if an evaluate answer strengthens or weakens the argument based on its outcome.

Alternative explanation

A competing possibility that challenges the original claim or conclusion.

Generalization

An argument that extends conclusions from a specific sample to a larger population.

Representativeness

The extent to which a sample accurately reflects the population it is derived from.

Counterexample

An example that contradicts a generalization, undermining its validity.

Critical reader

Someone who can evaluate the soundness of arguments and separate fact from assumption.

Weakening an argument

To make the conclusion less likely to be true by exposing its vulnerabilities.

Common strengthening patterns

Including confirming assumptions, adding evidence, or clarifying ambiguity.

Common weakening patterns

Including providing alternative explanations or showing insufficient evidence.

Plan/proposal argument

An argument recommending a specific action or plan.

Logical Reasoning (LR)

A section of the LSAT that assesses your ability to analyze and evaluate arguments.

Effective strengthening

Using information that directly supports the link between premises and conclusion.

Testing answer choices

Evaluating if an answer choice increases the likelihood of the conclusion.

Common mistakes in weakening

Confusing weakening with disproving, or picking answers that don't attack the conclusion.

Importance of assumptions

Identifying what must be true for an argument's reasoning to hold.

Connection to real life

Applying skills of evaluating persuasive claims in everyday contexts, such as advertising.

Frequency of Evaluate questions

These questions often relate to the key uncertainties in an argument's reasoning.

Mistaken assumptions in evaluate questions

Confusing a side point with the central issue of the argument’s reasoning.

Clarifying definitions

Strengthening can involve locking down meanings of ambiguous terms used in arguments.

Role of collectives in conclusions

An argument's conclusions may be weakened if the sample is not representative of the group.